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arXiv · 1809.08487

Josephson effect in a few-hole quantum dot

Joost Ridderbos·Matthias Brauns·Jie Shen·Folkert K. de Vries·Ang Li·Erik P. A. M. Bakkers·Alexander Brinkman·Floris A. Zwanenburg
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Abstract

We use a Ge-Si core-shell nanowire to realise a Josephson field-effect transistor with highly transparent contacts to superconducting leads. By changing the electric field we gain access to two distinct regimes not combined before in a single device: In the accumulation mode the device is highly transparent and the supercurrent is carried by multiple subbands, while near depletion supercurrent is carried by single-particle levels of a strongly coupled quantum dot operating in the few-hole regime. These results establish Ge-Si nanowires as an important platform for hybrid superconductor-semiconductor physics and Majorana fermions.

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Joost Ridderbos, Matthias Brauns, Jie Shen, Folkert K. de Vries, Ang Li, Erik P. A. M. Bakkers, Alexander Brinkman, Floris A. Zwanenburg. 2018-09-22. Josephson effect in a few-hole quantum dot. https://doi.org/10.1002/adma.201802257

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